| 摘要 |
PURPOSE:To provide a propelling jack which accurately generates a bending moment of a magnitude and direction which correspond to the attitude correction of a shield excavating machine concerned, which generates a large bending moment effectively even in case such is required, and which can be commonly used in various shield excavating machines having different number of propelling jacks and/or groups thereof and/or different positions of installation. CONSTITUTION:When the attitude of a shield excavating machine S is to be corrected, the bending moment till the target point A for operation is represented by the operational strength (r) and operational angle theta in a polar coordinates system at the center O of a circumferential line R. The thrust force distribution in each position of propelling jack is determined on both sides about the division into two parts made by a straight line tying two points B, C according to the linear gradient of the thrust force as determined by the operational strength (r) so that the max. thrust force is generated at point B, where the extension line of the operational angle theta intersects the circumferential line R, and the min. is generated at point C on the extension line R on the 180-deg. opposite side. The pressure target value for propelling jack is set according to the thrust force distribution determined. |
